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riadik2000 [5.3K]

4 years ago

10

All isotopes of technetium are radioactive, but they have widely varying half-lives. If an 800.0 g sample of technetium-99 decay

s to 100.0 g of technetium-99 in 639 000 y. What is it's half-life?

1 answer:

erica [24]4 years ago

3 0

The formula for A = Ao (1/2) ^ t/h
So sub in.
100 = 800 (1/2) ^ 639,000/?
That's all i can do lol

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20 points! Please help! Which graph represents the function?

Arte-miy333 [17]

I’m pretty sure they both are functions

6 0

4 years ago

A sound wave travels through iron at a rate of 5120\,\dfrac{\text{m}}{\text{s}}5120 s m 5120, start fraction, start text, m, e

klio [65]

Answer:

18432 km/h

Step-by-step explanation:

It is given that a sound wave travels through iron at a rate of 5120 m/s.

We know that

1 km = 1000 m

1 hour = 60 minutes

1 minutes = 60 second

Using these conversions we get

1 m = 0.001 km

1 hour = 3600 second

$5120\text{ m/s }=5120\times 0.001\times 3600\text{ km/h}$

$5120\text{ m/s }=18432\text{ km/h}$

Therefore, the sound wave travels through iron at a rate of 18432 km/h.

6 0

3 years ago

A regulation baseball field measures 90 feet between each base. What is the distance around the bases in yards?

Naddika [18.5K]

Home to 1st base = 90 ft
1st base to 2nd base = 90 ft
2nd base to 3rd base = 90 ft
3rd base to home = 90 ft
so we have a total of : (90 * 4) = 360 ft

there are 3 ft in 1 yd....
so in 360 ft, there are : 360/3 = 120 yds <==

or u could just figure it between each base....90 ft = (90/3) = 30 yds per base...and u have 4 bases....so that (4 * 30) = 120 yds

4 0

4 years ago

If x = -5 and y = x + 4, what ordered pair represents the solution? A. (5, -1) B. (-5, -1) C. (5, 1) D. (4, 4)

tekilochka [14]

B.) would be correct
(x,y)
x=-5
y=x+4
y=(-5)+4
y=-1
(-5,-1)

3 0

4 years ago

Mrs. Hinojosa head 75 ft of ribbon if each of the 18 students in her class gets an equal length of ribbon how long would each pi

Helen [10]

Answer:

4 1/6 ft

Step-by-step explanation:

Since each of the 18 students gets an equal length of ribbon, we need to divide the 75 ft of ribbon into 18 equal parts.

75/18= 4 1/6

Each student gets 4 1/6 ft of ribbon

4 0

3 years ago